1. Technical Field
The present invention pertains to sealing an entry to a structure to prevent intrusion of the elements (e.g., air and water) and, more particularly, but not by way of limitation, to a door and low profile door jamb sealing assembly that addresses both sealing of a space around the door from the passage of air and moisture and pressure equalization relative to outside air forces.
2. History of Related Art
The use of doors and door-frame assemblies in both residential and commercial buildings is a well-known, integral part of conventional building construction. It is also an area which must meet certain design and size limitations in order to allow disabled individuals to pass therethrough. The doors which permit passage or entry into a building from a space outside of the building are typically mounted within a door frame. Door-frame assemblies typically include a horizontal lower plate, also called a threshold or sill, a header, and two vertical members comprising the jamb. When closed, the door typically abuts against a door jamb stop on the vertical door jamb members and the header of the door-frame assembly. In its closed position within the vertical door jamb, the door is also positioned above a substantial portion of the sill member.
The combination of the header, vertical door jamb, and sill works together to perform multiple functions. The door-frame assembly provides structural support for, and surfaces for the pivotal swinging and sealing of, the door mounted thereto. A door-frame sill can raise the surface over which the door swings. A raised surface of the door-frame sill is designed to form a barrier to water infiltration beneath the door. In essence, it forms a dam which should hold back water infiltration. The header, vertical door jambs, and door-frame sill then function together to form a complete seal around the door which is designed to limit the infiltration of both air and moisture.
Prior-art door sealing systems have incorporated a variety of door-frame sill designs. Common styles of prior-art door-frame sills include elongated members which are formed into a variety of different shapes and sizes. These prior-art door-frame sills are typically adapted for positioning beneath swinging doors. Prior-alt door-frame sill designs generally include a first portion adapted for facing toward an interior of the building and a second portion facing outwardly toward an exterior of the building. The outwardly facing portion of the door-frame sill is generally designed to be a barrier to the passage of water beneath the door.
Door frames typically provide a requisite mounting for a door and surround the door's perimeter when the door is closed therein. Door frames are generally made of either wood or metal. Design parameters for door frames typically include width, length, cross-sectional shape, manner of securement to the surrounding building wall, and the manner of sealing three sides of the door with the jamb and header. The door-frame sill underlies the fourth, bottom side of the door, as referenced above.
To date, there have been various prior-art door sealing systems which have both advanced and improved the effectiveness of sealing a space around the edges of a door against the passage of air or moisture. One example of a prior-art door sealing system appears in U.S. Pat. No. 5,468,665. These prior-art door sealing systems often include gaskets and flanges which can be secured to the bottom of the door and/or to the door frame. While prior-art door sealing systems may be effective for some applications, it has been found that door assemblies used in buildings located in a high wind area, such as, for example, near the ocean, present even more difficult sealing problems.
To prevent the elements from penetrating the gap between the bottom of the door and the upper surface of the door-frame sill, a portion of the door-frame sill is usually raised above the level of the exterior landing approaching the door-frame sill, and raised above the structure's interior floor level. It is the rise of this door-frame sill that often causes the entry difficulties addressed by the Americans with Disabilities Act (“ADA”). The Fair Housing Amendments Act of 1988, P.L. 100-430, 102 Stat. 1619, amended the Fair Housing Act of 1968 to extend its coverage to housing discrimination on the basis of handicap. The core of the amended statute's provisions relating to housing discrimination on the basis of handicap appears in Section 804(f), codified at 42 U.S.C. §3604(f), which includes a subsection 3604(f)(3)(B), making it unlawful to refuse to make reasonable accommodations to afford a handicapped person equal opportunity to use and enjoy a dwelling.
Many prior-art door-frame sills are made of wood or metal. A primary consideration in the design of these prior-art door-frame sills is the ability to allow passage and withstand repeated exposure to inclement weather, particularly blowing wind and water. Metal door-frame sills, as opposed to wood door-frame sills, are generally better suited for resisting prolonged exposure to moisture. Some prior-art metal door-frame sills are formed with a hollow space beneath them to reduce cost and overall weight. Design parameters for door-frame sills typically include, for example, length, width, and cross-sectional shape. Because of the guidelines in the ADA and Fair Housing Act, door-frame sills in buildings are required to have a sufficiently low profile to provide easy access for passage of individuals in wheelchairs and individuals using walkers, crutches, or canes.
Specifically, many prior-art door sealing systems are rendered ineffective by high winds. Also, various prior-art door-sealing systems fail to effectively seal the door against high winds and moisture at a point where the door and the door-frame sill come together. This is particularly true with door-frame sill heights as required by ADA regulations and the like. The Fair Housing Act Design Manual at page 4.12 recommends that builders use a solution other than raising the level of the door-frame sill to prevent penetration of the elements.
It would be advantageous to provide a door sealing system including a door-frame sill that provides an improved system for preventing moisture and air infiltration, particularly in environments where high winds blow moisture against the outside surface of the door, and which further facilitates drainage of any water infiltrated into internal areas of the door-frame sill to prevent subsequent infiltration into the building.